Thomas Armitage came to America on 20 Nov 1635 on the "Expedition" from Gravesend, England to Barbados, age 24. Some records say he came to Lynn from Bristol, England, in 1635 aboard the "James". He was in Lynn, MA in 1636, in Sandwich, MA in 1637, in Stamford, CT in 1641, going to Oyster Bay, Long Island after that.

He was probably married twice, and had a son Manassah by his first wife, who studied at Cambridge and graduated from Harvard.

In 1650, Thomas Armitage was one of 50 original proprietors of Hempstead, Long Island. Most of them, like Thomas, were from Yorkshire county in northern England.